>
>Rich,
>There are several possible reasons why your measurements "varied all
>over the place."
>
>1. You have a defective SWR meter
>
A halfwave of 93 ohm coax was connected to a 50 ohm termination. The
50-ohm swr meter) was inserted at the end of the 93 ohm section and the
reading was 1:1. At the center of the halfwave section, the swr was
93/50 =1.86:1. . . The bottom-line is that when you have a matched
line, SWR-reading will not vary no matter where the meter is inserted.
However, with a mismatched line, placement of the SWR meter matters.
>2. You have a balanced load at the end of an unbalanced coax resulting
>in currents on the outer surface of the coax shield which are screwing
>up the measurements
>
>3. Your load is radiating and causing the same condition on the line as
>in item 2
>
>4. When you moved the SWR meter you did not make good connections to
>the meter and/or to the splice in the cable...see item 2
>
>5. The coax or connector(s) is bad...see item 2
>
>6. If you are calculating SWR from forward and reverse power
>measurements, you forgot to take the square root
>
>7. You misread the meter
>
>If you get different readings at different points on the line, you have
>a measurement error probably caused by one of the above choices.
>SWR on a mismatched line is the same from one end to the other (with
>slight modification due to cable losses).
>
>------------
>Jon,
>
>Emin = Emax defines a 1:1 VSWR so how can the voltage vary with a 1:1
>VSWR?
>
>--------
>
>Bob, W5AH
>
>--
>FAQ on WWW: http://www.contesting.com/ampsfaq.html
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>
- Rich..., 805.386.3734, www.vcnet.com/measures.
--
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